10 Answers
10

Cyclists shaving their legs is more tradition than anything else--there is a whole industry around creams, soaps, and salves. However, I'll defer to Sheldon Brown's explanation for a few acceptable reasons why they do it:

To prevent infection when crashing.

To pull off bandages more painlessly after dressing a wound.

To get a massage of the legs without hair pulling.

One reason I've often heard is 'To be more streamlined in the wind'--but I don't believe it!

We both neglected to mention the crucial reason: it makes us feel pretty. :P
–
ScottieAug 25 '10 at 20:16

1

Yeah, the answer must include prettiness :) Yeah, wind resistance is not the reason, but many beginners seem to thing so.
–
Johan DahlinAug 25 '10 at 20:19

5

I used to think air resistance didn't matter shaved legs vs no, but after watching that Discovery Channel Tour de France special(s) where they demonstrated how even clothing seam placement has effect on drag - I'm curious to see what effect leg hair really has on aero.
–
kkeilmanAug 25 '10 at 20:58

3

I started because of cleaning/crashing when I raced x-country. I continue because my wife thinks it's sexy and my cycling legs look hot. Really for all but the top riders on the Tour wind resistance is just what people say to justify it to themselves and others. I think you might go faster b/c you can see muscle definition and the placebo effect kicks in but that's it for mortals.
–
curtismchaleAug 25 '10 at 22:41

3

I can't find the source right now, but allegedly there were studies that showed that you get the least wind resistance if you shave your legs not completely, but leave stripes of hair in strategic places. I'm not making this up, I keep hearing it from veteran cycling commentators every now and then.
–
RegDwightSep 3 '10 at 0:12

I agree with Dustin's answer as the putative reasons usually cited, but I think at some level, it's a mark of the tribe.

Guys figure "if I shave my legs, other cyclists (and even some non-cyclists) will recognize me as a fellow cyclist." If being a cyclist is an important part of your identity, that'll be important to you. It is kind of cool to be able to pick someone out and strike up a conversation about cycling just based on their weird tan lines and/or shaven legs.

First, road rash is actually made worse by hairy legs. We all know that when you hit the pavement it acts like sandpaper scraping a layer off your skin. However, if you have hairy legs the hairs get pulled out by the root as well. This makes the road rash deeper where your skin actually comes into contact with the ground as well as making the surface area of the wound larger because of hairs that get pulled out around the actual contact area.

And second, while road rash isn't as much of a concern for mountain biking, there's an additional advantage there too. It's easier to wash the crud off after a ride. You can just hose your legs off out of your water bottle and watch the dirt come off in rivers.

One reason not yet mentioned is that in summer your legs feel cooler. But I think the No. 1 reason is psychological - it looks good and all the fast guys do it (sorry ladies, the shaving legs things for girls is so not an issue).